Derivatives and Hedging - Foreign Hedge (Details) - 3 months ended Mar. 31, 2018 $ in Millions	USD ($)	EUR (€)	USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of hedge of net investment of foreign operations		€ 220,000,000	$ 274
Effective portion of gain reclassified from Accumulated OCI into income	$ 3

The effective portion of gain reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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Balance Type:	credit
Period Type:	duration